Sharif Digital Repository

Re/Mo separation is studied by a new solvent extraction technique which is based on extraction mechanisms of the constituent metals. Based on McCabe-Thiele plots, a flow diagram has been proposed for separation and purification of Re over Mo. Re-recovery section of the diagram shows that Re is extracted when major amount of Mo is removed. For removal of the remained Mo, a two-stage extraction is required at pH = 2 and V a/V o = 1. In order to obtain Re, the resulted aqueous phase is stripped by adding sulfuric acid. According to the results, while more Re is extracted at less pH, optimum extraction of Mo happens at pH = 1.2. Re selectivity over Mo maximizes by approaching of the pH to zero  

The current study was aimed at developing a package of “model + algorithm” for the design of resin in pulp (RIP) and carbon in pulp (CIP) processes of gold, uranium, and base metals. For this purpose, we first formulated a double-resistance model for irreversible adsorption (accompanied by chemical reaction) in CSTRs, and modified the McKay et al. semi-analytical model for reversible uptake in a similar system. We then devised two algorithms for the design and optimization of reversible and irreversible RIP and CIP cascades. The developed algorithms were applied on the extraction of copper, uranium, and gold. The packages are able to specify the optimum number of stages, reactor volume (V),...